• The Plant Pathology Journal
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• v.38 no.6
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• pp.629-636
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• 2022

Colletotrichum species is known as the major causal pathogen of red pepper anthracnose in Korea and various groups of fungicides are registered for the management of the disease. However, the consistent use of fungicides has resulted in the development of resistance in many red pepper-growing areas of Korea. Effective management of the occurrence of fungicide resistance depends on constant monitoring and early detection. Thus, in this study, various methods such as agar dilution method (ADM), gene sequencing, allele-specific polymerase chain reaction (PCR), and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) were applied for the detection of benzimidazole resistance among 24 isolates of Colletotrichum acutatum s. lat. and Colletotrichum gloeosporioides s. lat. The result of the ADM showed that C. gloeosporioides s. lat. was classified into sensitive and resistant isolates to benomyl while C. acutatum s. lat. was insensitive at ≥1 ㎍/ml of benomyl. The sequence analysis of the β-tubulin gene showed the presence of a single nucleotide mutation at the 198th amino acid position of five isolates (16CACY14, 16CAYY19, 15HN5, 15KJ1, and 16CAYY7) of C. gloeosporioides s. lat. Allele-specific PCR and PCR-RFLP were used to detect point mutation at 198th amino acid position and this was done within a day unlike ADM which usually takes more than one week and thus saving time and resources that are essential in the fungicide resistance management in the field. Therefore, the molecular techniques established in this study can warrant early detection of benzimidazole fungicide resistance for the adoption of management strategies that can prevent yield losses among farmers.

• Korean Journal of Agricultural Science
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• v.48 no.4
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• pp.927-933
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• 2021

People have lived with and used animals for various purposes since the Paleolithic age. Therefore, animal bone research is interesting because it can infer the status of use, determine species, and ascertain the uses of animals that lived at the time. An analysis of ancient DNA was attempted to identify the species of ancient animal bones excavated from an archaeological site. Twelve animal bones from the Geumgwan Gaya period, excavated in Bonghwang-dong, Gimhae, were used in this study. After extracting DNA from the sample, polymerase chain reaction (PCR) gene amplification was performed. Species-specific primers of livestock groups such as pig, cattle, and deer were selected and used. This livestock group was a major source of protein for people who lived on the Korean Peninsula at that time. As a result, 11 sample species were identified. This study is contributes to the restoration of past life information by applying biological technologies to archaeological sites. It is also expected that such analyses of biological remains will ultimately be used to restore historical and cultural information.

• Journal of Microbiology
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• v.42 no.4
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• pp.365-368
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• 2004

The occurrence of strA-strB streptomycin-resistance genes within transposon Tn5393 was examined in Pseudomonas syringae pv. actinidiae, P. syringae pv. syringae, and P. marginalis, isolated from kiwifruit plants in Korea and Japan. PCR amplification with primers specific to strA-strB revealed that three of the tested Pseudomonas species harbored these genes for a streptomycin-resistance determinant. Tn5393, containing strA-strB, was also identified with PCR primers designed to amplify parts of tnpA, res, and tnpR. No IS elements were detected within tnpR, nor were they found in the intergenic region between tnpR and strA. Nucleotide sequence analysis indicated that the strA sequence of P. syringae pv. actinidiae contained a single nucleotide alteration at position 593 (CAA $\rightarrow$CGA), as compared to Tn5393a in P. syringae pv. syringae. This resulted in an amino acid change, from Gin to Arg.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.113.2-114
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• 2003

Five pepper-infecting potyviruses, Pepper mottle virus (PepMoV), Chilli veinal mottle virus (CVMV), Pepper veinal mottle virus (PVMV), Pepper severe mosaic virus (PSMV) and Tobacco each virus (TEV), are known filamentous virus and can be infected pepper crops systemically. To understand pathology and genome information of the five viruses on pepper plants, host reactions and sequences were compared to the 5 viruses. Five potyviruses were inoculated onto some typical cultivars of hot peppers and compared their symptoms, and virus accumulations. A set of degenerate primers for potyviruses were applied to 5 viruses and RT-PCR was performed. RT-PCR products containing partial nuclear inclusion b and coat protein (CP) genes were cloned. Then, oligo dT primer and species-specific primer were redesigned to amplify the C-terminal part of CP and 3' noncoding regions of each viruses. Sequences of the viruses were analyzed and compared to serological relationships among the viruses. The data can be useful for screening of potyviruses in pepper plants and pathogen-derived transgenic pepper plant development.

• Environmental Mutagens and Carcinogens
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• v.22 no.2
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• pp.76-82
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• 2002

In human U-937 cell exposed to ${\gamma}$-irradiation and $H_2O$$_2$, the level of mRNA efrpression in ceruloplasmin gene was measured by using comparative RT.PCR (reverse transcriptase-polymerase chain reaction). At the normal growth condition, the level of ceruloplasmin transcript was estimated as 8.2% and 0.0068% of hprt (hypoxantine phosphoribosyl transferase) transcript and of $\beta$-actin transcript, respectively. In U-937 cells exposed to a dose of 100 rad ${\gamma}$-irradiation, the level of ceruloplasmin transcript was increased about 2.7 and 1.6 fold compared to un-treated cell by using compensation with the levels of hprt and $\beta$-actin transcript. By contrast, the expression of ceruloplasmin gene in U-937 cells exposed to $H_2O$$_2$(50 $\mu$M, 24 h), was shown no significant difference compared to un-treated cell. These results indicated that the expression system of ceruloplasmin gene may react only some specific oxygen species, such as reactive oxygen species induced by ${\gamma}$-irradiation.

• Biotechnology and Bioprocess Engineering:BBE
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• v.8 no.3
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• pp.199-204
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• 2003

Among 59 Korean isolated, 20 were confirmed as members of the genus Bifidobaferium species based on gram staining, microscopic examination of cell morphology and the TLC method, The oxygen tolerance and antioxidative activities of these 20 Bifidobacterium strains and 5 standard Bifidobaferium strains were tested. All the strains demonstrated antioxidative activities as regards inhibiting linoleic acid peroxidation. The antioxidative activities of isolated and standard strains were found to range from 10.7-46.4% and from 10.7-22.2%, respectively. In addition, all tested strains exhibited a Scavenging ability on DPPH free radicals, range from 15-41% for the isolated strains and 8.3-22% for the standard strain. Accordingly. the isolated Bifidobarterium strains demonstrated higher antioxidative artivities than the 5 standa rd Bifidobarterium strains. On the base of grades for each test, HJL 7511 was identified 35 the best strain, followed by HJL 7501. 2 strains were identified with Polymerase Chain Reaction (PCR) assay using group-specific primers designed from the nucleotide Sequences of the 16S rRNA and internal transcribed spacer (ITS) regions of the Bifidobacteria. Based on the Sequencing results, HJL 7511 and HJL 7501 were identified as Bifidobacterium infantis.

• Journal of fish pathology
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• v.34 no.2
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• pp.133-140
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• 2021

With the recent isolation of a new betanodavirus in shellfish, Korean Shellfish Nervous Necrosis Virus (KSNNV), it has also been identified the reassortant KSNNV of two RNA segments, in which one segment is KSNNV genotype but the other one is known genotype. In this study, we confirmed that the ressortant KSNNVs obtained in previous screening study of our laboratory for betanodaviruses in shellfish were KS/RGNNV and RG/KSNNV type by performing two consecutive multiplex RT-PCR on each RNA1 and RNA2 segment (R1- and R2-discriminative multiplex two-step RT-PCR, respectively) to determine the genotype of each segment based on the size of amplicon. In the pathogenicity analysis, none of the reassortants induced specific external symptoms or mortality of VNN, but viruses of 2 × 10⁴~10⁵ copies/mg or more were detected at 14 days after injection (10⁷ copies/fish) in brain tissues of 4 species except for crucian carp and common carp among the 6 species of juvenile fish used. In addition, the histopathological features of weak but distinct vacuole formation were also found in the brain of these infected fish, but no difference was found between the two reassortants KS/RGNNV-KG and RG/KSNNV-CM.

• Biomedical Science Letters
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• v.26 no.3
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• pp.170-178
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• 2020

Mycobacterium tuberculosis (MTB) continues to be one of the main causative agents of tuberculosis (TB); moreover, the incidence of nontuberculous mycobacteria (NTM) infections has been rising gradually in both immunocompromised and immunocompetent patients. Precise and rapid detection and identification of MTB and NTM in respiratory specimens are thus important for MTB infection control. Molecular diagnostic methods based on the nucleic acid amplification test (NAAT) are known to be rapid, sensitive, and specific compared to the conventional acid-fast bacilli (AFB) smear and mycobacterial culture methods. In the present study, the clinical performances of three commercial molecular diagnostic assays, namely TB/NTM PCR (Biocore), MolecuTech Real MTB-ID^® (YD Diagnostics), and REBA Myco-ID^® (YD Diagnostics), were evaluated with a total of 92 respiratory specimens (22 AFB smear positives and 67 AFB smear negatives). The sensitivity and specificity of TB/NTM PCR were 100% and 75.81%, respectively. The corresponding values of MolecuTech Real MTB-ID^® and REBA Myco-ID^® were 56.52% and 90.32%, and 56.52% and 82.26%, respectively. TB/NTM PCR showed the highest sensitivity; however, the concordant rate was 10% compared with sequence analysis. Although MolecuTech Real MTB-ID^® showed lower sensitivity, its specificity was the highest among the three methods. REBA Myco-ID^® allowed accurate classification of NTM species; therefore, it was the most specific diagnostic method. Of the three PCR-based methods, MolecuTech Real MTB-ID^® showed the best performance. This method is expected to enable rapid and accurate identification of MTB and NTM.

• Journal of Microbiology
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• v.45 no.1
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• pp.69-74
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• 2007

Escherichia coli is a clonal species, and occurs as both commensal and pathogenic strains, which are normally classified on the basis of their O, H, and K antigens. The O-antigen (O-specific polysaccharide), which consists of a series of oligosaccharide (O-unit) repeats, contributes major antigenic variability to the cell surface. The O-antigen gene cluster of E. coli O66 was sequenced in this study. The genes putatively responsible for the biosynthesis of dTDP-6-deoxy-L-talose and GDP-mannose, as well as those responsible for the transfer of sugars and for O-unit processing were identified based on their homology. The function of the wzy gene was confirmed by the results of a mutation test. Genes specific for E. coli O66 were identified via PCR screening against representatives of 186 E. coli and Shigella O type strains. The comparison of intergenic sequences located between galF and the O-antigen gene cluster in a range of E. coli and Shigella showed that this region may perform an important function in the homologous recombination of the O-antigen gene clusters.

• Korean Journal of Agricultural Science
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• v.40 no.2
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• pp.115-121
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• 2013

Polymorphic bands of two fine-leaf zoysiagrass mutants (CNU 70-1, CNU 70-2) induced via a gamma-ray irradiation on seeds of Zoysia japonica were obtained by using randomly amplified polymorphic DNA (RAPD) primers. The genotype-specific fragments were then converted into PCR-based sequence characterized amplified region (SCAR) markers, which are now amenable to detecting them among other zoysiagrass species widely noticeable in Korea. The CNU 70-1-specific primer set amplified about 900 bp successfully, while the CNU 70-6 marker produced the expected 1,500 bp band, by which those markers were nominated by CNU 70-1_900 and CNU 70-6_1500 SCARs, respectively. The developed SCAR markers can be an applicable tool in sod industry where illegal appropriation hampers breeder's right and profits due to the turfgrass plant vegetatively propagating.